syslog = Syslog.open('myrep', Syslog::LOG_PID, Syslog::LOG_MAIL)

At apparently random intervals, syslog messes up with ident (first arg to #open) when writing log messages. This is a sample:

Sep 24 16:38:36 erebor myrep[25186]: MyRep Daemon
Sep 24 16:38:36 erebor myrep[25186]: Configuration: verbose = true / threshold = 0.0
Sep 24 16:39:00 erebor \237Çë- \220õÁ- [25186]: Entered attribute 1
Sep 24 16:39:00 erebor \237Çë- \220õÁ- [25186]: Entered attribute 2
....
Sep 24 17:11:09 erebor Èmݵ^A[25186]: Entered attribute 1349
Sep 24 17:11:09 erebor Èmݵ^A[25186]: Entered attribute 1350
Sep 24 17:11:09 erebor Èmݵ^A[25186]: Entered attribute 1351

The pid is still the same (since it keeps running), but the ident (myrep) was changed to some non-printable string at 16:39... then again at 17:11.

It seems unrelated to the priority I use, and it can happen anytime, even at the first log message.